ABB AC 800F

7 Functional Description of the Fieldbus Modules
7-13
• RAM: 256 Kbytes main memory for ASPC2 and 80C165,
ready for extension to 1 Mbytes. 256 Kbytes
transfer memory for 80C165 and AC 800F CPU
board. Both RAM domains protected by parity bits.
• Firmware memory: 512 Kbytes flash EPROM, 16-bit words,
reprogrammable while in the system, no additional
programming voltage required, direct
programming of AC 800F CPU board possible.
• Profibus data protection: All telegrams have a hamming distance (hd) of 4.
Complies with IEC 870-5-1. Special start/end bits,
non-slip synchronization, parity bit and control
byte.
• Plugging/removal
during operation Permissible, if slide lock is set properly, see
Section 7.1.
Static characteristics of the RS485 signals
Log. high: > + 0.2 V, differential between Pin 3 and Pin 8
Log. low: < - 0.2 V, differential between Pin 3 and Pin 8
Max. output voltage: ± 5 V, differential between Pin 3 and Pin 8
Max. output current: 250 mA (short-circuit)
Min. node impedance: 4 kohms
Max. number of nodes: 32 transmitters/receivers, expandable through
repeaters
Max. perm. cable length: 1200 m (depending on transmission rate)
Dynamic characteristics
Transmission rate 9600 bauds, 19.2 kbauds, 93.75 kbauds,
187,5 kbauds, 500 kbauds, 1500 kbauds,
3 Mbauds, 6 Mbauds, 12 Mbauds (configurable)